Before 25th April 2019 measurements in Kiruna was done by a riometer from La Jolla.
From 25th April 2019 30 and 38 MHz in Kiruna are extracted from RFsRio1 Wideband Spectral Riometer. From June 30th 2022 the riometer is situated in Tjautjas.
Quiet day curve is generated according to this algorithm
Median filtered with 400 seconds window
Quiet day curve is generated according to this algorithm